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DKA #565361 09/28/14 10:07 pm
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David,

Sorry to hear about the issues. Wish I could have been there and go figure couldn't make it and there was a tail wind.

I heard Tom and Mike had some misfortune also on the faired bike. I was glad to hear Mike was able to get the bike off the track without incident.

I will be ready for May with 2 bikes.



Chris


1955 BSA Bantam D1 Plunger
1956 BSA A10RR Street and LSR Bike
1961 BSA C15S
1966 BSA spitfire
1969 Triumph T100C
1970 Triumph TR6R
1970 Triumph TR6C
1972 BSA Lightning LSR Bike
1974 Triumph T150V
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DKA #565378 09/29/14 1:07 am
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Wow! David, sorry to hear of your problems. The weather sounded like it was perfect for some very fast runs. Thanks for the warning on the clutch plates. I'll stick with my ancient Norton plates.


God rides a Triumph but wishes it was a Norton.
DKA #565519 09/29/14 8:06 pm
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Sounds like a big difference in carbs, any idea's ?


1968 BSA Firebird
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XS 1100
1972 Rickman 125
konon #565549 09/29/14 10:37 pm
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At this point I'm shooting in the dark. Tomorrow I hope to take the lean carb totally apart and see if there could be anything to prevent it from flowing. I may send them off to get blue printed or look into other carbs altogether. PRT likes his Lectrons. The tuning is by an outside needle adjuster and that is so much better than taking those float bowls off 15 time a day. I have even investigated using throttle bodies and injectors (massive complications I think). I have the 34mm VMs that I ran for the last few years and I'll put them on the bike just to see if they can smooth out everything. I'll just keep digging until its figured out.

DKA #565550 09/29/14 11:20 pm
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In Remembrance
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I don't understand how a difference in jetting makes it vibrate..? Or is it a twingle..?

Ron

DKA #565595 09/30/14 9:15 am
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knuckle head
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Are the 38's Mikuni's? Pushrod Tom had fuel flow issues with 36MM Mikuni flat slides...On my bike's 36 MM Mikuni flat slides there a plastic disc over the main jet with several small holes in it.I guess it's some sort of sediment trap or flow diffuser...I enlarged the holes about 25 percent. However i did this before using them so can't say if it matters other than the engine has no fueling issues


79 T140D, 89 Honda 650NT ,61 A10 .On a bike you can out run the demons
"I don't know what the world may need
But a V8 engine is a good start for me
Think I'll drive to find a place, to be surly"
DKA #565632 09/30/14 2:21 pm
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Ron, There is one carb that will not enrichen with larger main jets. Which ever cylinder it is bolted to will not fire unless the float level is way down (lean). Raise the level up and it will not fire. Cold air pumping out of the cylinder. Run it low (but it's firing) and that cylinder is way lean and doesn't produce the power as the other cylinder. Hence the vibration.

HB, the 38s have a plastic ring and a tube that goes to the pilot jet. The main is not covered by the plastic, but it does hold the plastic in place.

I'm heading out there to dismantle the carb and see if there is an impediment somewhere. Biggest problem is that I don't know what I'm looking for (other than a solution)

DKA #565685 09/30/14 8:36 pm
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Hi,
Fuel restriction could be your problem. You could try measuring the amount of fuel into a container by isolating one carb by blocking the interconnecting fuel line between the two carbs, take out the drain plug of carb you are going to measure turn on the fuel tap for that carb for say 30 seconds, shut the tap and measure the amount of fuel you have caught in your container. then do the same procedure for the other carb, are they the same? If they are not the same the restriction is between the float bowl and the fuel tank in the container of the lesser amount. You may also benefit from upsizing your fuel taps and a larger tank breather for racing.

Cheers Brian



tr6c68
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DKA #565737 10/01/14 9:48 am
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Also check the breathers are not blocked, or the hoses from them are not crimped off. If it doesn't vent atmospheric pressure into the fuel bowl the fuel will not come out, lowering the fuel level may help it work for a while. I've seen a bike that would start then die because the guy had plugged the vent hose onto the bowl drain nipple effectively blocking it, only him riding it would convince him that that was all that was the matter with it smile


mark
DKA #565871 10/02/14 6:04 am
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Man I had one of those TSS and I loved it.
I hate selling things

DKA #565899 10/02/14 11:46 am
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In Remembrance
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What about the needle position..? The needle can restrict the main jet. Yes this has been tested..

Ron



Originally Posted by DKA
Ron, There is one carb that will not enrichen with larger main jets. Which ever cylinder it is bolted to will not fire unless the float level is way down (lean). Raise the level up and it will not fire. Cold air pumping out of the cylinder. Run it low (but it's firing) and that cylinder is way lean and doesn't produce the power as the other cylinder. Hence the vibration.

HB, the 38s have a plastic ring and a tube that goes to the pilot jet. The main is not covered by the plastic, but it does hold the plastic in place.

I'm heading out there to dismantle the carb and see if there is an impediment somewhere. Biggest problem is that I don't know what I'm looking for (other than a solution)

DKA #566340 10/05/14 7:36 pm
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Any news David? Really curious to know what you found.


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Sorry for the long wait to reply. Too much to do to get to spend time in the shop. I finally got around to replacing the clutch plates and will start to get everything back together for some testing. The issue with the carb is that from the moment it is kick started one cylinder is not firing. So it doesn't seem like it is a fuel feed issue. When I switch carbs side to side the problem goes with the carb. I've totally dismantled, cleaned, and blown out every orifice. Then reassembled the carbs. I made sure that both float levels were the same. Right now I have installed the 34 VMs from last year on it but have not tried starting it. I think Sudco offers blueprinting services so I'm thinking about sending both units to them.

I'll report back about the VMs.


DKA #576094 12/12/14 10:02 pm
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I pulled the valve covers off and found that we had been too greedy on cam lift and valve stem size. The short intake rocker arms at extreme lift must put some side loading on the valve. That side loading seemed to pull the valves and springs over into the "armpit" of the rockers. The rockers then were jammed and could not push the valves open. Gouges where the cap hit the rockers were clearly visible. The exhaust, at lower lift did not have this happen. This is what prevented me from making either of the two runs that I attempted. I contacted Nourish Engineering to see what their valve stem thickness was and the use a 7 mm compared to our 4.5mm stem dia. Next step is new guides and valves from Nourish and crank it up again.

I was testing new carbon impregnated steel clutch plates to see if they gave an advantage in grip. Turns out they just ate through my fiber plates and left thick fiber goop packed in the basket. Back to the old clutch!

DKA #576139 12/13/14 8:42 am
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Sounds like incorrect rocker geometry allowing the rocker tip to wipe too near the edge of the valve stem. May require different valve stem and or push rod lengths .


79 T140D, 89 Honda 650NT ,61 A10 .On a bike you can out run the demons
"I don't know what the world may need
But a V8 engine is a good start for me
Think I'll drive to find a place, to be surly"
DKA #576144 12/13/14 9:49 am
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Hope it didn't put excessive wear on the cam and tappets. (intake cam goes flat).

Last edited by konon; 12/13/14 9:51 am.

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HB,
I was thinking the same thing, but, not knowing aftermarket cam extremism, I kept quiet.

I had thought to say something like maybe, the possibility of adding some lash caps? Anybody else know what those are? Or, why they were even made?

Rickman #576157 12/13/14 12:18 pm
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Here is some pics. Not much room in there anyway. The springs and cap were pulled over just enough to jam. Probably high lifting rockers exert stronger side force than overhead cams. R&D continues...

[img:left][Linked Image][/img]


[img:left][Linked Image][/img]

Last edited by DKA; 12/13/14 12:22 pm.
DKA #576161 12/13/14 12:50 pm
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knuckle head
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Picture is worth a thousand words
Looks like the rockers are fouling the spring retainers....


79 T140D, 89 Honda 650NT ,61 A10 .On a bike you can out run the demons
"I don't know what the world may need
But a V8 engine is a good start for me
Think I'll drive to find a place, to be surly"
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Originally Posted by Hillbilly bike
Picture is worth a thousand words
Looks like the rockers are fouling the spring retainers....

Agreed.
Valve stems are too long, or the wrong spring retainers were used, or both.

..... Or? Aftermarket rocker arms were used???

Rickman #593680 04/05/15 8:48 pm
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After finding the bent valve and postulating that the stems were too thin, I called Nourish Engineering and bought their valves, guides, springs, caps and keepers. I figured if they work in the Nourish head they should work in the TSS. Rob replaced all those pieces and did a little rework of the rocker arms. He brought it by my house and we installed it and had it running smoothly in 4 hours. It sounded great. Rob only found 1 bent intake valve and it was bent above the guide. That valve was on the arm that the adjuster had broken a chip off the tip. He theorizes that the broken tip might have grabbed the valve and bent it. Anyway it's running beautiful now.

I'm going through all the systems to reconnect everything and hopefully by next weekend will have it out for a test drive.

I'm signed up for the May event and can't wait to see how it runs at speed.

DKA #593747 04/06/15 11:35 am
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I am using 5.5mm H*nda valves in my Rickman 8 valve. It originally had 7mm stems which looked massive given the head diameter. I made new spring keepers that used 600 four shims under a 5/16" shim cap to set the differential adjustment. A ball end screw at the pushrod sets the coarse adjustment.
[Linked Image]

DKA #684884 02/14/17 8:24 am
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Push rods need shortening.

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